Separation of cell type or components in the cells is required as the final purpose of a preparative tool for another analysis in diagnosis and treatment of the medical field and the research field. Now, there are many methods for classifying various kinds of cell types or components in the cells used in study rooms and clinical laboratories. A step of rapidly separating other kinds of particles, for example, virus, bacteria, cells and multicellular organism, is an essential step in various applicable fields of medical research, clinical diagnosis and environment analysis. Rapidly growing knowledge in a drug development and protein research allow researchers to quickly obtain many understanding about protein-protein interaction, cellular signal pathway and markers of metabolic processes. This information is difficult or impossible to be obtained by using a single protein detecting method, for example a traditional method such as ELISA or western blotting. Accordingly, the separation of cell type or components in the cells is much more required.
As the method for separating a certain target biomolecules from a biological sample such as blood plasma, methods using silica, glass fibers, anionic ion exchange resins or magnetic beads are known. Among them, according to the method using the magnetic beads, the target biomolecules is extracted: by inserting the magnetic beads having probes, which can be combined with the target biomolecules, on the surface into a sample solution to capture the target biomolecules, and then by separating the magnetic beads from the sample solution. The method for separating the target biomolecules by using the magnetic beads (bead based separation) was already commercialized, and broadly used for separating cells, proteins, nucleic acids or other biomolecules. For example, U.S. Pat. No. 6,893,881 discloses a method for separating a certain target cells by using paramagnetic beads coated with an antibody.
The magnetophoresis separation technology using a high gradient magnetic field (HGMS: high gradient magnetic separation) for separating the magnetic beads has been steadily studied for a long time due to its advantages of simple structure, high efficiency, easy used and no hydrolysis compared with dielectrophoresis. Another advantage of the magnetophoresis is that biological characteristics can be maintained by biocompatible bonds between the magnetic particles and bio analyte, and the force of the magnetophoresis is not affected by media.
The existing magnetophoresis method employs a magnetic energy source, which applies a magnetic field to separate a magnetic sample to be separated by magnetophoresis, and a magnetic material microstructure domain, which amplifies the gradient of the magnetic field applied by the external magnetic energy source; and separates the magnetic sample to be separated according to the gradient of the magnetic field by applying the magnetic field from the magnetic energy source. As one example, as shown in FIG. 1, Korean Patent Registration No. 10-0791036 discloses a method for separating pure carbon nano tubes by arranging a ferromagnetic material structure 40 besides a microfluidic channel 30, and by applying external magnetic field to the direction perpendicular to the flow of the carbon nanotube sample.
However, it was difficult to induce enough magnetic force for the fine particles with the gradient magnetic field generated from the apparatus used for the existing magnetophoresis method, and therefore, the efficiency for separating the fine particles was low and the time for separation was long. Accordingly, there was a problem that it is difficult to use the fine particles to be separated for separating and extracting from a sample.